The present invention relates to a developing apparatus for electrophotographic image forming equipment and, more particularly, to a developing apparatus of the type supplying a toner from a toner cartridge into a developing tank.
Generally, an electrophotographic copier, printer, facsimile machine or similar electrophotographic image forming apparatus forms a latent image representative of a document electrostatially on image carrier such as a photoconductive element. A toner carrier in the form of a developing roller, for example, is incorporated in the developing apparatus and supplies a developer, or toner, to the latent image to turn it into a toner image. A toner cartridge storing a fresh toner therein is removably or replaceably mounted on the developing tank so as to supply the toner into the tank. When the toner in the developing tank becomes scarce, the toner cartridge is replaced with a new toner cartridge. In the event of replacement of such a toner cartridge, the toner is apt to smear the operator's hands. To protect the operator's hands from smearing, there may be used a device which pushes out a toner from a toner cartridge into the developing tank, as disclosed in Japanese Utility Model Laid-Open Publication (Kokai) Nos. 23053/1989 and 24350/1989 by way of example.
The problem with the prior art approaches mentioned above is that they necessarily rely on some extra manual operation in supplying a toner from a toner cartridge into the developing tank. Specifically, the approach of Laid-Open Publication No. 23053/1989 is not practicable unless the operator rotates a toner pushing member by hand, while the approach of Laid-Open Publication No. 24350/1989 forces operator to cut a seal member while pressing a generally H-shaped member against the seal member.